After months of rumour and speculation, Microsoft has announced the release date for its universal operating system, Windows 10.

PC and tablets owners currently running Windows 7 or Windows 8.1 will be able to upgrade their systems to Windows 10 for free from 29 July. Consumers will then have an entire year to upgrade at no cost, after which time the company will start to charge (or release another new version, which is possible).

Unfortunately, only the release date of Windows 10 for OS for laptops, desktops and Windows tablets has been announced so far. We are still waiting for news on when Windows phone owners will also get their upgrade.

Pocket-lint understands, however, that the phone operating system was never intended to be released at the same time and that it would follow at a later date. Similarly, the Windows 10 update to Xbox One will be a much later release.

Along with Windows 10, computer and tablet users will get the PC version of Cortana - Microsoft's voice assistant - on 29 July, as well as Microsoft Edge, the company's new internet browser.